REFLECTOR: Alternate Air

[doug.holub at tx.rr.com]

I'm doing my alternate air this week, too. I've got a fiberglass elbow that connects to the air intake. I'm cutting a square flap out of the bottom of that, and then putting it back in with a springy hinge on one edge. (That springy hinge will be one or two plies of bid.) When there is normal air pressure at the intake, the flap will remain closed. If something clogs the air filter, the resulting vaccuum will open the flap.

After I thought of doing it this way, I checked online to see if anyone else had done it that way. I found a couple of production airplanes that had "automatic alternate air" which were springy hinged flaps. One was the SR22, I think. It also has a microswitch on the flap so that the pilot will know when alternate air is being used.

Doug Holub
Waiting on the propeller. 68/78 two blade Prince P-tip. I ordered it in January.

---- Andy Millin <amillin at sbcglobal.net> wrote: 
> For those running an intake filter.  I am looking for ideas on implementing
> an alternate air source.  I would love to hear and see (if you have the
> picture).
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> Thanks,
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> Andy
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> =====================================
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> Andy Millin
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> amillin at sbcglobal.net
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